A vidicon-OMA Raman technique will be developed and employed in the studies of human animal lenses. This technique, which facilitates the detection of Raman signals from partially opaque lenses and permits the acquisition of Raman and fluorescence data from lenses of living animals without retinal damage, may have a potential for clinical application in the diagnosis of early cataractogenesis. Both non-resonance and resonance CARS technique will be applied to the investigation of pigmented human lenses. During the next four years this proposed research has the following objectives: 1. To characterize by laser Raman scattering a late-appearing (senile) cataract in mouse. 2. To determine the effect of long-wave ultraviolet light on total sulfhydryl (protein-SH and glutathione-SH) in rabbit. 3. To determine if cataract promoters (hyperoxia, 3-aminotriazole) or cataract retarders (alpha-tocopherol, penicillamine) affects the rate of the 2SH yields SS conversion in vivo. 4. To make precise measurement of sulfhydryl and "fluorogens" profiles in intact human and animal lenses, and determine their age-related changes. 5. To interpret the dramatic difference found in lens aging between bovine and rat (or mouse) in terms of the three-dimensional structure of gamma-crystallin. 6. To determine if the oxidation of protein sulfhydryl to form disulfide crosslinks is involved in human senile cataract.